Lasting jack positioning device



1931. E. E. FOSTER LASTING JACK POSITIONING DEVICE Filed Sept. 13, 1928 5 Sheets-Sheet 1 Ov l-PQI HI I HHHHH w A l Oct. 27, 1931. E. E. FOSTER LASTING JACK POSITIONING DEVICE Filed Sept. 1:5, 1928 5 Sheets-Sheet z fizz/6771707":

Ema/rd EFOJ Der:

Oct. 27, 1931. FOSTER 1,829,000

LASTING JACK POSITIONING DEVICE Filed Sept. 13, 1928 5 Sheets-Sheet 5 1711067176071 Edwczm E. F0 5236?:

Oct. 27, 1931. E. E. FOSTER LASTING JACK POSITIONING DEVICE Filed Sept. 13, 1928 5 Sheets-Sheet 4 v 1777067112577. Eoltuard EJ 22509),

Oct. 27, 1931.

E. E. FOSTER LASTING JACK POSITIONING DEVICE Filed Sept. 15, 1928 5 Sheets-Sheet 5 I 1 1 l I 1 frz/vefi/f/orv Edwardfl [2) 627671 Patented Oct. 27, 1931 EDWARD E. FOSTER, BEVERLY, MASSACHUSETTS, ASSIGNOR,"BY MESNE ASSTGN- MENTS, TO HOODItUBBER COMPANY, INC., 01 WILMINGTON, DELAWARE, A CQB-.

, BORATIQNOF DELAWARE;

Las'rme JACK POSITIQN'INGDEVICE Application filed September 13, 1928. Serial No. 805,751.

This invention relates to an apparatus for positioning a last or the like, and particularly' to a lasting jack positioning device.

.The object of the invention is to provide a device; which preferably may be used in conneotion with an endless conveyor mechanism for the purpose of supporting a shoe last and automatically positioningthe same so that the'last and shoe under construction thereon will be delivered to the various operatives who are to perform the successive operations of; constructing the shoe, in a position that will be'the, most convenient for said operatives to start their particularoperation, the

device, furthermore, being so constructed that no matter what'the position of the last is 1 when each successive operative finishes his,or her, particular operation, it will be delivered to the succeeding operative in the position desired, 7 V

Another object of the invention is to so 2 construct the jack that the last thereon may be moved manually by. the operatives while each successive operation is being performed thereon without interference from the mechanism which automatically positions the last holder as it is delivered to the operative.

The device of this invention is designed to be used in conne tion with the convevor mechanism and method of manufacturing footwear illustrated and described in an application 'SerialNo. 232.419 filed November.

10, 1927. and also in an application Serial 'No. 237.719 filed December 5, 1927. the jack of the present invention being substituted forthe; jack illustrated in each of said applications,

The invention consist-sin an apparatus for manufacturing shoes and the like as set forthin the following specification and particularly as pointed out in the claims thereof.

Referring to the'drawings 'Figure 1 is afront elevation of a lasting 2 jackpositioning device embodying .my invention, portions 'of the conveyor utilized for driving the device and portions of the camsfor operating the device being broken awav toisave space in the drawings.

Fig, 2 is an enlarged front elevation of a mechanism illustrated in Fig. 5 is a detail horizontal section taken on the line 5+5 of Fig. 2. c

Fig. 6 is a detail section taken on line 66, Fig.3.

Like numerals refer to like parts through out the several viewsof the drawings.

In the drawings, 10 is the frame and 11 is an endless chain conveyor meshanism, either of which may be of any desiredconstructi'on, and either of which may be constructed as illustrated and described in either of the applications hereinbefore mentioned, to which reference may be had for a complete description- Fastened in any suitable manner to the endless chain 11 is a movable frame 12 form,- ing a portion of a lasting jack 13. The frame 12 is provided with guide rollers 14 at its upper end and with guide rollers 15 at its lower end, said rollers travelling in tracks 16. and

17 respectively fast to the frame 10. The jack 13 embodies therein a bracket 18 having bearings 19. and 20 provided therein between which a rocking member 21 is pivotally mounted, and a holder 22 for a shoe last 23 is in turn pivotally mounted upon the rocking member 21. The rocking member 21 is rigidly secured to a stud 24 being pinned to a head portion25 of said stud, and the stud 24 is, rotatably mounted in the bearing 19' of the jack whereby the member 21 being fastened thereto is rotatable about an axial line E. I

A helical gear 26 is rigidlv fastened'to the stud 24 and said gear meshes with and is driven by a helical gear 27 which is rigidly fastened to a shaft 28. one end of which is rotatably mounted in the bearing portion 19 of the bracket 18 and'the other end of said shaft being rotatablv mounted in a bearing portion 29 of sa d bracket. A spur rear 30 is rigidly fastened to the shaft 28 and meshes withand is driven by a ring gear 31 which,

in turn, is rigidly fastened to a flange 32 forming part of a hub portion 33 of a lever which is pivotally mounted in a bearing 35 forming a part of the bracket 18. A cam roll is rotatably mounted at the outer end of the lever 34 and a rocking motion is imparted to said lever 34 within the bracket 18 by a plurality of cams which are rigidly fastened to the frame 10.

' In Fig. l of the drawings portions of two of said cams A and Bare illustrated, the former consisting of two cam members a, and the latter cam consisting of two cam memhere 5. All of the cams are constructed in a k similar manner and the members thereof are preferably so spaced that they will be provided with a relatively narrow space 37 through which the cam roll 36 may pass from the cam, and the relatively wide space 38 through which the cam roll 36 may enter the cam. The lever 34 is so constructed thatit may swing through an arc of approximately 90 as illustrated at m, Fig. 1, and the members of each cam are so spaced at the wide end of the cam, that as the jack 13 is moved in this space and the last can be rotated by the operator without hindrance by the mechanism hereinbefore described.

At their narrow ends the cam members are so positioned that when the cam roll 36 passes from the cam through the narrow space 37 1 thereof, the rocking member 21 will be correctly positioned; the extreme upper position to which the last holder 22 may be rocked by said rocking member being illustrated 1n full lines in Fig. 4, and the extreme lower position to which said last holder may be rocked being illustrated in dotted lines in said figure. In order to prevent the lever 34 from being easily displaced after the cam v roll 36 thereon has been discharged through the narrow opening in one of the cams, a friction mechanism has been provided which embodies therein a plurality of teeth 39 which are formed upon the lever 34 adjacent a to the hub portion thereof, and said teeth its pivot within the rocking member 21 by mechanism which operates as follows :-The last holder 22 (Fig. 6) is rigidly fastened to a shaft 42 which thus forms a part thereof and is rotatably mounted in the rocking member 21 and thus the holder 22 is rotatable about an axial line G, Figs. 2 and 3.

.A helical gear 43 is rigidly fastened to the shaft 42 and said gear meshes with and is driven by a helical gear 44 which is rigidly fastened to a shaft 45 concentric with the stud 24 and axis E. A head portion 46 of the shaft 45 is located within the head portion of the stud 24. The shaft is rotatably mounted in a bushing 45 provided therefor in the bearing portion 20 of the bracket 18.

A helical gear 47 (Figs. 4 and 5) is rigidly fastened to the shaft 45 and meshes with and is driven by a helical gear 48, Fig. 3 rigidly fastened to a shaft 49, one end of which is rotatably mounted in the bearing portion 20 of the bracket 18, the other end of said shaft being rotatably mounted in a bearing 50 also provided in the bracket 18. A spur gear 51 rigidly fastened to the shaft 49 and meshes with and is driven by a spur gear 52 rigidly fastened to a shaft 53. A hub portion of the gear 52 is mounted to rotate in a bearing 54 forming apart of the bracket 18. At its other end the shaft 53 has a bevel gear 55 rigidly fastened thereto and a hub portion 56 of the bevel gear 55 is rotatably mounted in the hub portion 33 of the lever 34. The bevel gear 55 meshes with and is driven by a pair of oppositely disposed bevel pinions 57 (Fig. 4) which rotate idly upon studs 58 mounted in the ring gear 31. The pinions 57 mesh with and are driven by a bevel gear 59, which is driven by a bevel gear 60 rigidly mounted on the hub portion of said gear 59, which rotates idly on the shaft 53.

The bevel gear 60 meshes with and is driven by a gear segment 61 which is rigidly fastened to a shaft 62 rotatably mounted in suitable bearings provided in the bracket 18. A lever 63 is rigidly fastened to the lower extremity of the shaft 62 and said lever has a cam roll 64 rotatably mounted thereon and provided for the purpose of engaging a plurality of cams such as are illustrated at C and D. The cams C and D embody therein cam members 0 and (Z respectively and are similar in construction to the cams A and B. The cams C and D are each provided with a wide entrance space and a narrow discharge space and are so arranged that no matter what the position is of the lever 63. as the jack moves with the conveyor chain, the cam roll 64 will. engage the cams as the jack advances and position the last automatically without the aid of the operative In the following claims the part 22 and its shaft 42 constitute a holder for a last and the movable frame 12, bracket 18 and rocking member 21 constitute a support for said A cap 65 isprovided for the bracket; 18,

m thereby providing a covering for the bevel gears.

The general operation, of the mechanism. hereinbefore described is as. follows :As-

suming that there is atplurality of the jacks 13 either fastened to or driven by. the endless conveyor chain ,11 and that'each jack has a last mounted thereon upon which there is a shoe under construction, it is desirable for the convenience of the various operatives, that the last shall'be delivered to them in such a position that they can perform their particular operation inthe least possible time and with a minimum amountv of efiort.

With this in mind, the'various' cams are aranged so that they will deliver the jack in front of the operative with thelast thereon in the position desired,'and it is possible that this position mayvary with each operative.

As the jack is fed toward. the right in Fig. 1,-

the cam rolls 3.6 and 64 of the levers 34 and 63 respectively will engage the members of the different cams as A and B and C and D. In thecase of the cam'roll 36, when the same engagesiits: cam, as A or B, a rocking movement will be imparted to the lever 34, cansing the ring gear 31 to rotate the shaft 28, which, in turn, will rotate the stud 24, thereby rotating the rocking member 21 and the latter may be rotated approximately 180 or from the position illustrated in full lines in Fig. 4 to that illustrated in dotted lines. in said figure. At the same time that'the rocking member 21 is; being rotated upon-its axis,

. the last holder 22 is controlled upon its axis in the rocking member 21 by reason of the fact that the cam roll 64 will engage one or another of the cam membersv of the cams as.

C andD which" arelocated within its path,-

and the rocking movement of the lever 63 will transmit through the gear segment 61, bevel gears 60 and 59, bevel pinions 57, bevel gear 55,, shaft 53,spur gears 52 and 51, shaft 49, spiral gears 48 and 47, shaft and spiral 1 gears 44 and 43 a rotary movement to the shaft 42 which comprises. the axis of the last holder 22, and when the cam roll 62 finally passes from engagement with .the cam, the last 23 will be positioned to suit the operative, 7

When the operative is performing the operation upon the shoe, she, or he, may move the last within the limits permittedby the rotative movements of the last holder 22 and x, rocking member 21 for the reason thatat this time the cam rolls '36 and-64 are disengaged from the camsby whichthe mechanism is: O erated automatically, and no matter what t e position is of the cam rolls 36 and 64 atthe completion of the operation, as the lasting jack passes from one operative toward the succeeding operative, said cam rolls will eventually pass into the influence of the suc ceeding cam andeventually reposition the last for the succeeding operative. v

The gear segment 61, bevel gears. 60, 59 and. 5 5, pinions.- 57 and ring: gear 31 constitute, a differential gear mechanism and the bevel gears (30, 59 and 55 and pinions 57 may be rotated by means of the lever '63 and gear seg-' ment 61 without causing any rotative movement of the ring gear 31. WVhen, however, the rocking member 21is rotated by its: cam lever 34 through its attached ring gear, intermediate shafts and gears, the pinions 57 vwill travel with the ring gear about the differential axis 53 and because the bevel gear 59 is inhibited from rotatingby the bevel gear segment 6.1 through the engaged pinion 60 the said pinions 57 will roll upon the face of the arrested gear 59, and combined with the aforesaid travel of the pinions 57 impart rovtation to the gear 55. The shaft 53 being rotated by the gear 55 will rotate gear 52 keyed tosaid shaft, thereby driving the shaft 49' 'whichrotates the shaft 45 in synchronism and as a unit with the rocking member 21. It will be readily seen by those skilled in the art that no rotation will beimparted to, the last holder 22 through its shaft 42 by the rotation of the rocking member 21. Inversely, the rotation of the last holder 22 on its shaft 42 will not impart rotary motion to the rocking member 21.

In the foregoing specification it will be understood that one embodiment of my in'ven-- tion is described and that embodiment illustrated in the different figures of the drawings. The invention, however, is notto be limited to this particular embodiment thereof. For example, the endless chain conveyor 11 might be dispensed with and any other means formoving thelastholder and its support substituted forsaid chain conveyor, or i the last holder andits support could be moved from one positionto another asby pushing the last. holder support along the tracks 16 and 17 or their equivalents without departing from the spirit of this invention.

Furthermore, the last holder and its support maybe stationary as to bodily travelling movement or transposition thereof, and'the last and its holder rotated and/or revolved about an aXis or axes by the mechanismhereinbefore described, or other suitable mechanism, without departing from the spirit of my invention. 7 1 I I claim: r 1

. 1. An apparatus for'positioninga last hav-.

- ing in combination, a holder for a. last, asup- Eli) port :fiorsaid holder, mechanism for changing the position of said last holder relatively tosaid support, means for moving said support, locally-mounted means for actuating said mechanism as a result of the movement of the support past said locally-mounted means, and means for lightly holding the said holder, in the position on said support to which it is thus moved, after the said support has passed out of association with the said locally-mounted means.-

2. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, locally-mounted actuating means,1neans for moving the said support past the said locally-mounted means, and mechanism actuated thereby for moving the said holder to a determinate position with relation to said support from random positions theretofore occupied by the said holder with relation to the said support.

3. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, and mechanism for rotating said last holder on said support about a plurality of axes, said mechanism being actuated by the movement of said support.

at. An apparatus for positioning a last having, in combinatioma holder for a last, a support on which said holder is mounted for movement about an axis, and mechanism for rotating said last holder on said support about another axis approximately parallel to the bottom of said last, said mechanism being rendered operable by the movement of said support.

5. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, mechanism for rotating said last holder on said support about oneaxis in one direction and in another direction about another axis extending transversely of said first-named axis, and actuating means for 7 said mechanism, said mechanism being actuated and then released from the actuating means by the movement of said support.

'6. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, mechanism for rotating said last holder on saidsupport about either one of two axes extending transversely of each other, and actuating means for said mechanism, said mechanism being actuated by the movement of said support.

7. An apparatus for positioning a last having, incombination, a holder for a last, a support for said holder, and mechanism for rotating said last holderon said support about two axes extending transversely of each other, said mechanism being actuated by the movementof said support.

8. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, and mechanism includhaving, in combination, a holder for a last,

a support for said holder, and mechanism including a differential gear for rotating said last holder on said support about an axis ap proximately normal to the bottom of said last.

11. An apparatus for positioning a last having, in combination, a holder for a last,

a support for said holder, and mechanism including a differentlal gear for rotating said last holder on said support about an axis approximately parallel to the bottom of said last.

12. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, and mechanism including a differential gear for rotating said last holder on said support about one axis in one direction and in another direction about another axis extending transversely of said firm-named axis.

13. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, and mechanism including a differential gear for rotating said last holder on said support about either one ofhtwo axes extending transversely of each 0t, er.

14. An apparatus for positioning a last' having, in combination, a holder for a last, a support for said holder, and mechanism including a differential gear for rotating said last holder on said'support about two axes extending transversely of each other.

15. An apparatus for positioning a last having, in combination, a holder for a last, a support for said holder, and mechanism including a differential gear for changing the position of said last holder relatively to said support, said mechanism being rendered operable by the movement of said support.

16. An apparatus for manufacturing shoes sition of said holder .and last by movement thereof relative to the conveyor about a plurality of axes.

ill

Ila

I 18. An apparatus for manufacturing shoes and the like having, in combination, a, conveyor, a holder for a last and a support therefor driven by said conveyor in an endless ath and means actuated by the movement 0 the conveyor to changethe position of said holder and'last by movement thereof relative to the conveyor about a'plurality of axes. I I

19. 'An apparatus for manufacturing shoes and the like having, in combination, a conveyor, a holder for a last and a supportingmember therefor, driven by said conveyor in an endless path, and means to change the positions of said supporting member relatively to the conveyor and said holder relatively to saidmember. I I

' 20. An apparatus for manufacturing shoes and the like having, in combination, a con veyor, a supporting member driven by said,

conveyor in an'endless path, alast holder pivotaliy mounted upon said member, and 1 means to change the positionof said member relatively to the conveyor;

21. An apparatus for manufacturing shoes and thelike having, in combination, a conveyor, a supporting member driven b said conveyor in an endless path, a last older pivotally mounted upon saidmember, and

v means actuated by movement of the conveyor to change the positionofsaid member relatively to the conveyor. I I

22. An apparatus for manufacturing shoes andthe like having, in combination, a con veylor, a'. lasting jack driven'by said conveyor inan endless path and embodying therein a rocking member, a last holder upon said rocking member, and means actuated by movement of the conveyor to change the position f of said last holder relatively to the making 40 member. H

23. An apparatus for manufacturing shoes and the like having, in combination, a conveyor,a;last ing jack driven by said conveyor and embodying therein a rocking member, a,

last holder pivotally-mounted upon said rock-v ing member, and means tomove saidholder upon the pivot thereof. to change the position of s'a'idholder relatively to. the conveyor.

I 24. An apparatus for manufacturing shoes and thelike having, in combination, a conveyor, a lasting jack driven by said conveyor and embodying therein a rocking member, means to impart a rockmgmovement to sald .member, a last holder pivotally mounted upon said rocking member, and means to move said I holder upon the pivot thereof to change-the positionof the holder relatively to the conveyor. 4 I I 25. An apparatusv for manufacturing shoes and the like having,1incombination, .a frame,

aconveyormounted upon said frame, a lasting jack driven by said conveyor and embodying therein a rocking member, a last holder upon said rockingmember, and means embodying 'therein'a cam'upon said 'fr'ame'to change the position of said last holder upon said rocking member. I I

' 26. An ap'paratus'for manufacturingshoes and the like having, in combination, a frame, a conveyor mounted upon said frame, a lasting jack driven by said conveyor embodying therein a rocking member, means embodying therein a cam upon said frame to impart a rocking movement to said member, a last holder pivotally' mounted upon said rocking .member, and means embodying therein a cam upon said frame to change theposition of said holder upon said rocking member.

27. An apparatus for manufacturing shoes and the like having, in combination, a conveyor, a support for a last driven by said conveyor, and means embodying therein a differential gear mechanism tochangethe po-.

sition of said support and last relatively to the conveyor.

28. An apparatus for manufacturing shoes and the like having, in" combination, a'conveyor, a lasting jack driven by said conveyor and embodying therein a rocking member, a

last holder upon said rocking member, and means embodying therein a differential gear mechanism to change the position of said last holder relatively to the conveyor. 2

' 29. An apparatus formanufacturing shoes and the like having, in combination, a conveyor, a lasting jack driven by said conveyor andembodying therein'arocking memthe rocking member. I I

.31. An apparatus for manufacturing shoes and the like having, incombination, a conveyor, a lasting jack driven by said conveyor and embodying therein a rocking member, a last holderupon said rockingmember, a

differential gear mechanism operatively con nected to said rocking memberoand embodymg therein a'drlving gear, means to rotate said driving gear, and means to actuate said last-named means. I I

32..An apparatus for manufacturingshoes and the like havmg, in comb1nat1on,a conveyor, a lasting jack driven by said conveyor and embodying therein a rocking member,

a last holder upon said rocking member, a differential gear mechanism operatively connectedto said rocking member and embodyingthereina driving gear, a lever fast to -11 and embodying'therein a rocking member,

a last holder upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodyingl therein a driving gear, means to rotate sai driving gear, and means for actuating said and embodying therein a rocking member,

last-named means.

3%. An apparatus for manufacturing shoes and the like having, in LOl'l'lblIltltlOIl, a conveyor, a lasting jack driven by said conveyor a last holder upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodying therein a driving gear, a lever fast to said driving gear, and a cam for operating said lever.

' 35. An apparatus for manufacturing shoes and the like having, in combination, a conveyor, a lasting jack driven by said conveyor and embodying therein a rocking member, a last holder upon said rocking member, a diiferential gear mechanism operatively con nected to said roking member and embodying therein a driving gear, means to rotate said driving gear, means to actuate said lastnamed means, another driving gear embodied in said differential gear mechanism and operatively connected to said last holder, means to rotate said last-named driving gear, and means for actuating .said lastnamed means, g V 36. An apparatus for manufacturing shoes and the like having, in combination, a con- Ceyor, a lasting jack driven by said conveyor and embodying therein a rocking member, a

last holder upon said rocking member, a differential gear mechanism operatively connected to said rocking member and embodying therein a driving gear, a lever to rotate said driving gear, a cam to actuate said lever, another driving gear embodied in. said differential gear mechanism and operatively connected to said last holder, a lever fast to said last-named driving gear, and a cam for operating said last-named lever.

37. An apparatus for manufacturing shoes and the like having, in combination, a conveyor,- a lasting jack driven by said conveyor and embodying therein a rocking member, a last holder upon said rocking member, a differential gear mechanism embodying therein a driving gear, gears operatively connecting said driving gear and said rocking member, a lever fast to said driving gear, and a cam for rocking said lever.

38. An apparatus for manufacturing shoes and the like hav1ng, 1n combination, a conveyor, a lasting ack driven by said conveyor and embodying therein a rocking member,

a lastholder upon said rocking member, a differential gear mechanism embodying therein a driving gear, gears operatively connecting said driving gear and said last holder, a lever fast to said driving gear, and,

a cam for rocking said lever.

39. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, means embodying therein a gear mechanism to impart a rocking movement to said rocking member, and means embodying adilferential gear mechanism to rotate said last holder upon said rocking member.

40. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, means embodying therein a gear mechanism to impart a rocking movement to said rocking member, and means including a differential gear mechanism to rotate said last hold-er upon the rocking member.

121. A jack for alast having in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder rotatably mounted upon said rocking memher, a differential gear mechanism operatively connected to said rocking member and embodving therein a driving gear, means to retate said driving gear, and'means for actuating said last-named means.

42. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder rotatably mounted upon said rocking memher, a differential gear mechanism operatively connected to said rocking member and em bodying therein a driving gear, a lever fast to said driving gear, and a cam for operating said lever.

43. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, means embodying therein a differential gear mechanism to rotate said last holder upon said rocking member, and means to rock the rocking member upon the bracket.

44. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, 9. last holder mounted upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodying therein a driving gear, means to rotate said driving gear, and means for actuating said last-named means.

45. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodying therein a driving gear, a lever fast to said driving gear, and a cam for operating said lever.

46. A jack for a last having, incombination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodying therein a driving gear, means to rotate said driving gear, means to actuate said lastnamed means, another driving gear embodied in said differential gear mechanism and operatively connected to said rocking member, means to rotate said last-named driving gear and means for actuating said last-named means. Y

47. A jack for a last having, in combination, a bracket, a rocking member pivotally mounted upon said bracket, a last holder mounted upon said rocking member, a differential gear mechanism operatively connected to said last holder and embodying therein a driving gear, a lever to rotate said driving gear, a cam to actuate said lever, another driving gear embodied in said difle'rential gear mechanism and operatively connected to said rocking member, a lever fast to said last-named driving gear, and a cam for operating said last-named lever.

In testimony whereof I have hereunto set my hand.

EDW'ARD E. FOSTER. 

